Graphene, a well-known two-dimensional(2 D) material, has sparked broad enthusiasm in both scientific and industrial communities in these years, due to its exceptional electrical, thermal, mechanical, and versatile pr...Graphene, a well-known two-dimensional(2 D) material, has sparked broad enthusiasm in both scientific and industrial communities in these years, due to its exceptional electrical, thermal, mechanical, and versatile properties. However, many properties and applications of graphene are layer-number dependent. The preparation of high-quality graphene with controlled layer numbers is full of challenge, since the layer number varies much with the synthesis routes and relevant experimental conditions. Hence, there is an urgent need to improve the layer-number controllability of graphene preparation. Generally, graphene can be prepared by two complementary approaches: "top-down" and "bottom-up". Since they have their own advantages, the recent advances in the layer-number tunable preparation of high-quality graphene are separately studied from the two aspects in this review, especially those dedicated to single parameter. Some effective strategies are discussed in detail, mainly including 1) supercritical-CO2 assisted sonication, electrochemical exfoliation of graphite intercalation compounds, and layer-by-layer thinning with plasma or laser, for "top-down" graphene;2) chemical vapor deposition(CVD) on dual-metal substrate, ion-implantation CVD, layer-by-layer CVD, plasma-enhanced CVD, layered-double-hydroxides template-assisted CVD;and 3) graphite-enclosure assisted epitaxial growth and pulsed-magnetron-sputtering assisted physical vapor deposition for "bottom-up" graphene on various substrates. In addition, the respective advantages of graphene with different layer numbers in properties and applications are also presented. Finally, the contribution concludes with some important perspectives on the remained challenges and future perspectives.展开更多
Traditional Chinese Medicine has been very popular in Taiwan in the past.TCM was incorporated in the National Insurance since 1995.Starting 2012,all new TCM physicians had to be graduated from TCM Department in Medica...Traditional Chinese Medicine has been very popular in Taiwan in the past.TCM was incorporated in the National Insurance since 1995.Starting 2012,all new TCM physicians had to be graduated from TCM Department in Medical University.Currently,there are 6,442 TCM physicians practiced in 3,372 clinics and 95 hospitals.TCM only accounts for less than 4%of total National Health展开更多
质量源于设计(Quality by Design, QbD)是指在可靠的科学和质量风险管理基础之上,预先定义好目标并强调对产品与工艺的理解及工艺控制的一个系统的研发方法。QbD理念强调产品的质量无法通过检验赋予,而应该通过设计赋予。在该理念指导下...质量源于设计(Quality by Design, QbD)是指在可靠的科学和质量风险管理基础之上,预先定义好目标并强调对产品与工艺的理解及工艺控制的一个系统的研发方法。QbD理念强调产品的质量无法通过检验赋予,而应该通过设计赋予。在该理念指导下,制药工业应该将质量风险管理与产品和生产工艺深度结合,运用过程分析技术,建立适当的控制策略,促进产品在整个生命周期内持续改进和创新。展开更多
基金Sponsored by the JSPS Invitational Fellow ship for Research in Japan (Grant No. L18516)the National Natural Science Foundation of China(Grant No. 51273148)
文摘Graphene, a well-known two-dimensional(2 D) material, has sparked broad enthusiasm in both scientific and industrial communities in these years, due to its exceptional electrical, thermal, mechanical, and versatile properties. However, many properties and applications of graphene are layer-number dependent. The preparation of high-quality graphene with controlled layer numbers is full of challenge, since the layer number varies much with the synthesis routes and relevant experimental conditions. Hence, there is an urgent need to improve the layer-number controllability of graphene preparation. Generally, graphene can be prepared by two complementary approaches: "top-down" and "bottom-up". Since they have their own advantages, the recent advances in the layer-number tunable preparation of high-quality graphene are separately studied from the two aspects in this review, especially those dedicated to single parameter. Some effective strategies are discussed in detail, mainly including 1) supercritical-CO2 assisted sonication, electrochemical exfoliation of graphite intercalation compounds, and layer-by-layer thinning with plasma or laser, for "top-down" graphene;2) chemical vapor deposition(CVD) on dual-metal substrate, ion-implantation CVD, layer-by-layer CVD, plasma-enhanced CVD, layered-double-hydroxides template-assisted CVD;and 3) graphite-enclosure assisted epitaxial growth and pulsed-magnetron-sputtering assisted physical vapor deposition for "bottom-up" graphene on various substrates. In addition, the respective advantages of graphene with different layer numbers in properties and applications are also presented. Finally, the contribution concludes with some important perspectives on the remained challenges and future perspectives.
文摘Traditional Chinese Medicine has been very popular in Taiwan in the past.TCM was incorporated in the National Insurance since 1995.Starting 2012,all new TCM physicians had to be graduated from TCM Department in Medical University.Currently,there are 6,442 TCM physicians practiced in 3,372 clinics and 95 hospitals.TCM only accounts for less than 4%of total National Health
文摘质量源于设计(Quality by Design, QbD)是指在可靠的科学和质量风险管理基础之上,预先定义好目标并强调对产品与工艺的理解及工艺控制的一个系统的研发方法。QbD理念强调产品的质量无法通过检验赋予,而应该通过设计赋予。在该理念指导下,制药工业应该将质量风险管理与产品和生产工艺深度结合,运用过程分析技术,建立适当的控制策略,促进产品在整个生命周期内持续改进和创新。
